1. Field of the Invention
The present invention relates to a content browsing system, a content browsing method, and computer program product.
2. Description of the Related Art
Nowadays, with widespread use of mobile phones with camera, digital video cameras or the like, improvement in performance of personal computers, and increase in network speed, it has become common to capture multimedia information, such as audio, and a still image and a moving image except for text, in a personal computer (PC) to utilize, transmit and receive, and share the multimedia information on a Web environment. The amount of such multimedia information is increasing on the Web environment. To utilize a vast amount of multimedia information on networks effectively, it is important that a user can browse information (content) according to his/her utilization purpose efficiently. Preferably, the user can control an amount of information to be displayed or the type of media to be utilized according to browsing state or his/her preference.
Web browsing requires easy access to desired information. Therefore, it is important that a relationship between an outline of the entire content and details of the content is easily understandable. For example, if content of individual items can be simultaneously browsed in a screen of a list of search results, improvement in search efficiency can be expected.
It is also required that information is displayed flexibly in a form suitable for user's purpose, preference, and browsing state. For example, in the case of browsing a report about business trip, a boss of a reporter is likely to wish to view an agenda for a meeting on the business trip, and an accountant is likely to wish to view utilized transportations and transportation expenses. It is also likely that detailed text information with images is desired on a desktop PC, while an outline of the information is desired on a mobile terminal. Therefore, it is desirable that a user can control an amount of text, a size of an image, balance between the both, or the like flexibly.
On the other hand, fundamental operation interfaces in a current Web environment include scrolling and anchor clicking. By utilizing these operations properly, a user can perform browsing while displaying large (broad area) content on a screen, or while moving from one page to another among hyperlinked related pages by anchor clicking. Thus, browsing efficiency is enhanced.
However, viewability is reduced with an increase in amount of information to be displayed on a single page even if scrolling is utilized. When one page is divided into pieces and they are linked, a user jumps to another page to browse a linked page, and therefore, context of browsing is lost. A number of jumps between links not only makes it difficult to return to an original page but also makes it difficult to find positioning of a portion on which attention is currently focused in the entire context.
As described above, it is difficult to control a display form flexibly according to user's purpose, preference, and browsing state in the current Web environment. It is necessary to preliminarily assume display forms and prepare a plurality of pages corresponding to the display forms to realize such flexible control in the general Web environment, which results in complicated page structure.
In recent years, a zooming user interface (ZUI) that is an operation interface for controlling the level of detail of what is displayed on a screen continuously has been researched and developed variously.
There has been proposed a conventional technology, in which, when one of respective pages or images arranged two-dimensionally is selected and zoomed, only the page or image is displayed largely while a peripheral display remains unchanged. Reference may be had to, for example, Perlin, K. and Fox, D.: Pad: “An alternative approach to the computer interference,” Proceedings of SIGGRAPH'93, pp. 57-64 (1993), Bederson, B. B. and Hollan, J. D.: Pad++: “A Zooming Graphical Interface for Exploring Alternate Interface Physics,” Proceedings of UIST'94, pp. 17-26 (1994), and Bederson, B. B., Meyer, J. and Good, L.: Jazz: “An Extensible Zoomable User Interface Graphics Toolkit in Java,” Proceedings of UIST'00, pp. 171-180 (2000).
There has been proposed another conventional technology, in which candidates of display formats for an object to be handled are presented on a menu and the object is zoomed automatically in such an extent that it can be displayed with a proper level of detail by a display format selected by a user. Reference may be had to, for example, Holmquista, L. E. and Ahlbergb, C.: Flip Zooming: “A Practical Focus+Context Approach to Visualizing Large Data Sets,” Proc. HCI International'97, pp. 763-766 (1997), and Woodruff, A., Landay, J. and Stonebraker, M.: “Goal-Directed Zoom,” Proceedings of CHI'98, pp. 305-306 (1998).
Besides, there has been proposed still another conventional technology related to zooming from a plurality of viewpoints. Reference may be had to, for example, Sarkar, M., Snibbe, S. S., Tversky, O. J., and Reiss, S. P., M.: Stretching the Rubber Sheet: “A Metaphor for Viewing Large Layouts on Small Screens,” Proceedings of UIST'93, pp. 81-91 (1993).
There has been proposed still another conventional technology related to zooming in response to a moving speed of a mouse cursor. Reference may be had to, for example, Igarashi, T and Hinckley, K.: “Speed-dependent Automatic Zooming for Efficient Document Navigation,” WISS 2000, pages (2000).
According to these technologies, an overview and enlarged detail can be displayed together in one page, which contributes to improvement in browsing efficiency.
However, these technologies have been fundamentally developed based upon intention to provide an application for displaying content with a zooming function. For example, for realizing such a configuration that, when upper text in meaning is zoomed in, lower detailed text appears, or display balance between text and an image associated with each other is controlled in a linking manner, a behavior program including information about the structure of content to be subjected to zooming operation has to be incorporated into an application in advance. Therefore, it is generally impossible to zoom any content except for content having a structure that is assumed for the application. Accordingly, these technologies are improper for performing the zooming operation versatilely on a Web environment where there are contents having various structures.
The applicant has proposed, in Japanese Patent Application No. 2005-044515, another conventional technology in which zooming is applied to content that contains various objects to continuously change a display state of the objects. According to the conventional technology, a media object such as text, still image, moving image, and sound is taken as a target to be subjected to zoom operation, and a font size, an image size, reproduction time, etc., are continuously controlled according to the zoom operation. Thus, it is possible to perform the zoom operation for the entire content or for each of the objects that constitute the content.
However, the above conventional technology still has room for improvement.
FIG. 4 is an example of evaluation information, such as ranking score, popularity level, difficulty level, and publication year, of literatures retrieved from a library using a certain search keyword. The ranking score is, for example, a value indicating a degree of relevance between a search keyword and literature summary. The ranking score is calculated by a method such as Tf/Idf, and is assumed to be a value from 0.0 to 1.0. The popularity level can be automatically calculated based on lending times of literatures, evaluation values determined by library users or librarians, or any combination thereof. The difficulty level is calculated based on the evaluation values determined by users and librarians. The difficulty level is assumed to be a value from 1.0 to 5.0. That is, the ranking score, the popularity level and the difficulty level can be defined as evaluation information.
FIG. 12 is an example of results obtained by conventional zoom-in/zoom-out operation for all search results. In (a) of FIG. 12, a search result screen displays, as the search results, a list of only the titles of the literatures arranged in descending order of the ranking score shown in FIG. 4. If zooming (zoom-in operation) is performed for the entire list of the search results, information items other than the title such as author and publisher appear as shown in (b) and (c) of FIG. 12.
That is, in the conventional technology, all literatures are evenly zoomed regardless of the evaluation values as shown in FIG. 12, and evaluation information other than a predetermined evaluation value (ranking score in FIG. 12) cannot be acquired.